Mapping the nature of diversity: a landmark project reveals a remarkable correspondence between indigenous land use and the survival of natural areas.

• Author: Ayres, Ed

Maps may be famously variable in accuracy, but generally speaking they are no more "objective" than are movies, novels, speeches, or paintings. Even if painstakingly accurate, they heavily reflect the interests of those who paid to have them made. Those interests may be political, commercial, or scientific. In the second half of the twentieth century, world maps emphasized the preoccupations of the Cold War, with a primary emphasis on international borders. The globes we had in our classrooms showed a world made up of nations. Until recently, most maps showed very little of what some of us now believe to be critical to the future of life: the boundaries of bioregions, watersheds, forests, ice caps, and biodiversity hotspots--and the principal ocean currents, wind currents, oceanic fisheries, and migratory flyways. In one of the offices at Worldwatch, there's a large map of North America showing nothing but the distribution of underground water. In World Watch, over the years, we've published maps of the globa l distribution of infectious diseases, war, slavery, refugee flows, and electric light as seen from space. The advancing technologies of Geographic Information Systems (GIS), combining the use of satellite imaging and digital data, have made these tasks easier by replacing laborious cartographic handwork with a capacity to superimpose maps of various elements showing how these elements may be related.

The fold-out map on the following pages is a product of one of the most remarkable mapmaking efforts of recent times. It is a simplified version of a monumental map created under the direction of a nonprofit group called the Center for the Support of Native Lands, and produced in its final form by the National Geographic Society. It was designed to exhibit two main categories of information: the distribution of cultural diversity in Central America and southern Mexico, and the distribution of forest and marine resources in that region. By superimposing these sets of information in detail, the map strongly confirms a hypothesis that has long been familiar to environmentalists and anthropologists alike: that there is a significant correlation of some kind between cultural diversity and biological diversity. That may seem obvious, as the homogenizing impacts of globalization are fueled and further exacerbated by a stripping of forests for cattle-ranching, plantations, and urban development. But in the past, the kind of data available to...